On the basis of a consideration of the problems associated with the treatment of Parkinsonism with L-DOPA and L-DOPA plus decarboxylase inhibitors, it appears worthwhile to investigate the possible application of the metal chelates of L-DOPA as an alternate approach. The objective of this proposal is to undertake an exploratory study on the development of candidate chelates of L-DOPA with Cu(II), Zn(II) and Mg(II) that could be investigated for an optimal transport of intact L- DOPA into the brain. The stoichiometry of metal-ligand interaction, the thermodynamic stability and solubility of the chelates in aqueous and non-aqueous media will be investigated by potentiometric, absorption spectral and other necessary physical chemical methods. On the basis of the conditions developed in this study, radio-labeled L-DOPA chelates of Cu(II), Zn(II) and Mg(II) will be prepared and investigated in animal experiments in order to determine the transport of intact L-DOPA into the brain.